What is the maple syrup process?

Submitted by sorghumco on Tue, 03/18/2008 - 15:16

How we make Maple Syrup at Sandhill Farm

Tapping. Note: we tap soft (silver) maple trees – since that is what we have on our land; most of the commercial maple syrup on the market comes from hard maple trees in Canada and northern US. We have planted hard maple trees – but they are very slow growing; our 20 year old trees will probably take another 10 years before we can tap them.
How do you find maple trees? One way is to look up at the canopy – the maple trees have swollen reddish buds – after awhile, the eye picks them out readily (by now, I know where all the trees on our land are). Then you inspect the trunk of the tree to find the scars from previous years’ tapping – new taps should be about 4” away from old ones; also, we prefer to tap the south sides of trees because when the sun shines, it warms that side of the tree and makes it flow more. We have been tapping some of our trees for 20 years so they are pockmarked by grown over old holes and it is a challenge to find the right spot. When we do, we drill a 5/16” hole 2-3” deep with an electric cordless drill (we used to use a brace & bit – but the cordless is faster/easier). Another person hammers in a plastic tap (we buy them from maple sugaring supply places. Then attach a plastic tube to the tap and the other end into a bucket on the ground.

How many taps? The rule of thumb is that a tree needs to be at least 12” in diameter (at chest height) to be tapped. A tree that is more than 20” can have 2 taps and over 28”, 3 taps. We run the tubes from one tree into the same bucket – usually, a 5 gal bucket. We do not put more than 3 taps in a tree.

Renay sucking maple sap from a tree.

What makes the sap flow? as with many life processes, it is still somewhat mysterious and magical to me. The sap flows when the daytime temperature is above freezing and nights are below freezing. Why? It is kind of like a pump: the sap in the sapwood of the tree (not the cambium) expands with higher temps thus creating pressure, which causes the sap to flow into our buckets to relieve the pressure (if there are any wounds in the tree, it flows from there too). Low temps at night make the sap contract thereby creating a vacuum, causing the sap to be sucked up into the sapwood from the roots (where it was stored in the winter). Then the rising temps make the sap expand again, etc. But wait! We have freezing/thawing temperatures in December & January as well. Does the sap flow then too? No. the sap rises in the spring (I’ve been told that you can also collect sap in the fall – we have never tried it) – apparently, the inner energy in the trees begins to stir according to some inner clock (when the geese start flying north?). when it’s spring, the sap rises…

How fast does it flow? It depends on the weather/temperatures. Occasionally, a tree will fill a 5 gal bucket in a day, but it more often takes a week or more. In the same time, one tree may yield 5 gal of sap while a neighboring tree will give only 1. why? I have no idea! We generally put out about 100 taps in about 50 trees every year these days. Our total annual yield has been between 16 and 76 quarts of syrup in the last decade – which translates to between10 and 60 gallons of sap per tree. In our operation, it takes about 2 hours of work for every quart of maple syrup.

How do we cook? History: we first cookeded maple in 1988: Ann & Ceilee decided to tap a big old maple near our pond as a home schooling project. They cooked it down on our kitchen stove – it took forever, but it worked! We had just purchased another property, which had a grove of large maple trees and we realized we could use our sorghum cooking pan to increase the speed and efficiency of cooking.
The next year we tapped approximately 20 trees and cooked it in the sorghum pan (a stainless steel pan 3’x16’ over an open wood fire) - it was so much faster! We have been cooking it there until 2 years ago when we converted our sorghum cooking operation to a wood fired steam boiler system. The boiler uses water to make steam which passes through copper tubes inside the juice to boil it; however, we can’t use this process because during the time we process maple, we have freezing temperatures and so we would have to drain the boiler and all the tubes every time it was going to freeze – WAY TOO MUCH WORK! Solution? We took the old sorghum pan and cut it down to 3’x 9’ and moved it to a separate space in the same building (not quite that simple since we had to build a firebox with firebrick in a new location for the pan. Maple was the one to be moved since it is a small part of what we process in Sugar Shack: sorghum is our main income producing business: we make about 7-800 gallons, and 1-200 gal of honey compared to 5-20 gallons of maple).

Back to how we cook. With sorghum, we cook the raw juice into the finished syrup in a continuous process – all in the same day (or even hours). I assume some do the same with maple – but we don’t(I have never watched anyone else cook maple). we do not sell any of our maple – it is only for our own use – and our pan is not designed to finish cooking small batches. When we have enough sap, we cook it down and then leave some in the bottom of the pan so it will not burn. When we have more sap we add it to the pan and cook it again – so the same sap can get boiled 4 or more times before we have enough that we can take it off and finish it in pots on our wood stove in the kitchen, where we can control the heat and concentrate the syrup w/o burning it. The last step is to ladle it into quart jars for storage for the rest of the year – we do not filter it and so we have “sediment/maple sand” in the bottom of our jars – it tastes the same as the rest of the syrup, but if we were to sell it, we would probably have to filter it.

Cooking together. When dancing rabbit eco-village became our neighbors 10 years ago, some folks there were interested in making maple syrup. they tapped some trees on their land as well as on neighbors. They bring the sap to our place since we have the facility to cook it efficiently. We divide the syrup by the # of hours we contribute and/or the sap we bring in. when alyson moved to dr, she became the point person for the maple energy since she had family experience making it in new England. Now she lives at redearth farms and coordinates the maple energy at redearth & dancing rabbit.